Motion picture record



Aug. 3, 1937.

G. w. WALTON 2,088,732

MOTION PICTURE RECORD Original Filed Oct. 19, 1929 Patented Aug. 3, 1937 UNITED STATES PATENT OFFICE MOTION PICTURE RECORD George William Walton, London, England Original application October 19, 1929, Serial No. 400,883. Divided and this application August 23, 1935, Serial No. 37,584. In Great Britain October 25, 1928 4 Claims.

lates to motion picture records which may be produced with the aid of the aforesaid methods and apparatus.

If an ordinary picture be regarded as composed of a large number of elemental areas of a size depending upon the degree of definition required in an image and such that the detail within any of these areas can, for this degree of definition, be neglected, the novel form of image or stixograph with which the present invention is concerned is an image in which the elemental images, that is to say the images of the elemental areas of the object, are deployed in such a way that they do not overlap one another when viewed in a direction perpendicular 35 to that of the deployment. Usually the picture can be regarded as divided into a number of strips, each composed of one single row of the,

aforesaid elemental areas, and in this case the elemental areas of each strip of the object are 0 represented in the stixograph by elemental imway of example.

one dimensional image resulting from the transformation of the two dimensional image shown in Fig. 1,

Figs. 3 and 4 are views in side elevation and plan respectively of a reflecting echelon device for transforming a two dimensional image into a one dimensional image, or vice versa,

Figs. 5 and 6 are views in side elevation and plan respectively of a refracting echelon device, Figs. '7 and 8 are similar views of a modified form of refracting echelon device,

Figs. 9 and 10 are similar views of a modified form of stepped refracting echelon device,

Figs. 11 and 12 are diagrammatic views showing the way in which records of animated scenes may be obtained, and

Fig. 13 is a diagrammatic view of. apparatus for forming a one dimensional image.

Referring particularly to Figs. 1 and 2, Fig. 1 shows a two dimensional image, picture, scene or representation, which it is desired to transform into a one dimensional or stixograph type image. During the transformation, the picture is divided into any number of strips asb to gh the width and number of strips being decided by the degree of definition required. After such sub-division, all points lying on a line :r-a: across the Width. can be represented by the line :r:r having an intensity which is the average of the intensities of all points in it, and therefore each strip only requires definition in its length. If the strips ab to gh in Fig. 1 are deployed as in Fig. 2 to form images a1b1, c1-d1, e1f1, g'1-h1, then as long as there is definition within the length m to hl, the image 121 to hi is equivalent of Fig. 1, for practical purposes, as it contains representations of all the elements of Fig. 1. For example the line a:-:v of Fig. 1 appears at arr-4:1 in Fig. 2. Fig. 2 is a one dimensional arrangement of Fig. 1 which is two dimensional, and in this arrangement x1a:1 may be vanishingly short or infinitely long without affecting the efficacy of Fig. 2 as a picture or image so long as the density or brightness of 121-421 in the image of Fig. 2 is representative of the average density or brightness of :c-a: in the original of Fig. 1.

The stixograph of Fig. 2 can be derived from the two dimensional image of Fig. 1, or vice versa,

by means of an echelon device which may be reflecting, refracting or combined reflecting and refracting.

Figs. 3 and 4 show a reflecting echelon device, Fig. 3 being a view in side elevation and Fig. 4 a View in plan. In Fig. 3 the vertical faces I are mirrors. In Fig. 4 a pencil of light represented by arrow 2 having a depth covering all the reflecting surfaces I, is thrown on to those surfaces at an angle, a section of the incident pencil being reflected by each surface. As each successive surface is further away than the preceding one, the sections of the pencil are reflected with lateral displacement, which by suitable size of steps, angle of incidence and width of pencil can be such that the reflected sections 3, 4, 5 do not overlap. If, therefore, the cross section of the incident pencil is represented by Fig. 1, the

cross section of the reflected light will be represented by Fig. 2.

With the type of reflector shown in Figs. 3 and 4, there is the disadvantage that the length of the light travel is different for each step of the reflector, but this may be remedied by successive reflection from two or more stepped surfaces so arranged that the lateral displacements of the successive surfaces are preferably additive.

Fig. 5 shows a refracting echelon device in side elevation, Fig. 6 being a plan view of the same device. Light passing through the steps is laterally displaced by amounts dependent on the thickness of material traversed, so that the issuing sections 3, I, 5 of the entering pencil a are deployed, as in Fig. 2. Refraction may take place in one or more stages, with the displacement of the successive stages additive, and further the stages may be arranged so that the length of path through the system is constant at all points, thereby facilitating the focusing of an image.

Fig. 7, shows another form of echelon refrac-tor, in side elevation, Fig. 8 being a view in plan thereof. This refractor consists of a stack of prisms 6 to i l of increasing angles, each step giving a different angle of deviation. If the prisms are arranged in increasing order as shown, they serve to arrange the issuing light sections (each section representing a strip of the object) as in Fig. 2.

Fig. 9 shows another stepped refractor in front elevation, Fig. 10 being a view in plan thereof. The steps are lenticular in shape and staggered preferably in a direction at right angles to the mean optical axis. An object or image at If, similar to Fig. 1, is independently examined by each step and deployed images of sections of I: are formed at 3, I, 5 etc.

There are numerous possible forms of echelon reflectors, refractors, and combinations, but the essential feature of each form is that there shall be definite steps in the device having linear or angular displacement between the steps, preferably, but not essentially, of some regular order of displacement.

The stixograph or one dimensional image of the type illustrated in Fig. 2 is of great practical utility, as by its use very compact records can be made of scenes or pictures, and, further, it is of even greater value in recording changing scenes, in that a truly continuous record may be made in contrast to the ordinary cinematograph record which is intermittent. The manner in which this is accomplished is shown in Figs. 11 and 12.

In Fig. 11 i is the record material, such as photographic film plate or paper, on which a stixograph err-b1, Cl-d1, 01-41, gi-h1 is focused. If after exposing the film to this image the filin be moved upward, a second image 02-472, 02-412. ea-fz, g2h2 can be produced and so on. This record is of the intermittent type and is therefore of the same character as and can be dealt with in a similar way to ordinary cinematograph films. If the material 1' is moved intermittently and exposed to the image a1h1 each time it is stationary, there will be found upon i after development a series of separate stixographs Ill-hi, (Ir-ha etc. Such a record differs from an ordinary cinematograph record only in that the individual pictures are one dimensional instead of two dimensional. If the pictures ai--h1, 02-h: etc. are impressed succesively without any movement of the scene or point in the scene, and if the position and aspect of the apparatus relative to the scene is kept constant, then a point k1, representative of an elemental area at about point k in Fig. 1, will appear in each picture in the same relative position. As the film 1' moves the points ki, 16:, k3, hr in each picture will lie in a line parallel to the direction of movement of i and consequently the film i need not move intermittently nor need the picture be exposed intermittently, for the film i can be given a movement preferably constant and along a straight line, and the points Zn, In: etc. will trace a line on the record, the intensity of the impression at any point of that line being proportional to the intensity of point k of Fig. 1 at some particular moment. The density or brightness of such a line is obviously a continuous and true record of the density or brightness of the point k of Fig. 1 and of that point only. The same also applies to every other point in the line image.

Fig. 12 shows such a record, the sections a1b1, 01-411, e1--J1 and g1h1 being representative of corresponding sections of the image, that is individual strips a-b, cd, e-f, g--h respectively of the original two dimensional image or scene shown in Fig. 1, and for a condition of no movement in scene or apparatus the points in each section will trace a number of parallel lines, as shown only in section a1-b1. Should a point in the scene move, say horizontally in Fig. 1, then during such movement, the corresponding point in the image of Fig. 12, due to the movement of the point combined with the steady downward movement of the record, will trace a line which is no longer parallel to the direction of movement of the record. Assuming rectilinear direction and a constant speed of movement of the record 1', a point moving horizontally to the right from p to q in Fig. 1 at a constant speed in one direction will trace a straight line, such as pr, (11 in Fig. 12, and another point moving horizontally from r to s in Fig. 1 in an opposite direction and at a decreasing speed will trace a curve n to .91 in Fig. 12. A point moving vertically downwards in Fig. 1 at a constant speed will move from one line to another in succession and will, therefore, appear successively in adjacent sections a1-b1, c1d1 etc. of Fig. 12 as the short lines 7', l, m and n, which will lie in a straight line in the record and be all of the same length.

Another point moving vertically upward at an increasing speed will appear as the lines '0, :c, y and 2, which lie in a curve, the line 12 being the longest and the others being of successively shorter lengths. Any other direction of movement of a point in the scene will be recorded as a compound of vertical and horizontal movements. Within the limit of definition imposed by the number of strips into which a scene may be divided, that is the number of sections, such as (ll-b1, c1--d1 etc. of Fig. 12. and that definition which the recording surface can satisfactorily accommodate, every point of the scene may be moving individually in different directions and paths, rectilinear curved or irregular, and at wholly different speeds increasing, decreasing, constant or irregular, and each point will simultaneously trace on the record a characteristic and individual pattern, and yet the different patterns will in no way interfere with each other, for should a line cross another on the record for instance as m, m and n, in in Fig. 12, the point of crossing is a recordat the moment when one point is obscured by the other in the scene being rec ed.

Sill

Another way of regarding the matter is that each of the vertical lines of the stixograph record of Fig. 12 is a record of the brightness or density of one elemental area of the object. The vertical dimension is the time dimension and therefore if the elemental area in question remains of constant brightness then the line in Fig. 12 representing that elemental area will be of constant brightness or density. If the brightness of the elemental area changes then the brightness or density of the line will change correspondingly.

A picture record as described may be said to record the position of a point in a scene in one dimension of the record, the other dimension corresponding to time and the whole record recording change of position in time. It is preferable that the line image being recorded should be very narrow (in the direction of movement of the record) in order to improve the quality of the record and also to shorten it, for instance it may be a tenth of a millimetre wide, in which case three millimetres of length could contain thirty line pictures. It may be said that there are more, for the record is continuous. Sixteen pictures per second are capable of recording scenes having ordinary movement from which it follows that the picture record need only move at a rate of two to three millimetres per second. In contrast with the ordinary cinematograph film using one foot per second, there is great advantage and also apparatus for intermittent movement and exposure is not required.

In order that the record shall be of a convenlent width, one dimension of the image may be reduced relative to the other. The reduced dimension is preferably the horizontal dimension of Fig. 1 and the horizontal length of Fig. 2 and the width of the film necessary for recording is thus correspondingly reduced. The limit to this reduction will be the ability of the surface to record the definition required which is determined by the size of the grain of the emulsion if a photographic record is used. This reduction is also of advantage in television apparatus.

For the purpose of making a photographic record as described, the moving recording surface is arranged at the point where a line image is formed by an echelon device in combination with a lens system-together with a system of reels, rollers and guides to accommodate and to traverse the recording surface over the line image.

In reproducing the picture by projection, a similar device may be used, the record being traversed and suitably illuminated so that a reconstructed two dimensional picture will be thrown on a screen disposed to receive it.

As described, the picture record is in the form of a strip but this is by no means necessary for it may take the form of a disc similar to a gramophone record, again that of a cylinder. or any other form which ailords a surface on which a line image can be impressed whilst that surface is given a suitable traversing motion as described with reference to Fig. 12.- The record may be transparent or opaque and during reproduction may be illuminated by light passing through the record'and onto the optical system, or by light which is reflected by the record on to the optical system.

An arrangement for producing a vstixograph record is shown in Fig. 13 in which I2 is a lens system, l3 the echelon device which forms a line image at i. A photo-sensitive film may be moved continuously in the plane of the stixograph image in a direction perpendicular to the plane of the paper in Fig. 13. i

The reproducer may be similar, a light source being provided to the right of the film i.

Such subject matter as is disclosed but not claimed herein or in parent application, Serial No. 400,883, is claimed in my application Serial No. 115,048, filed December 9, 1936, for Improvements in picture representation and improvements in television and in the recording and reproducing of pictures, which application is also a division of application Serial No. 400,883.

I claim:

1. In a motion picture film bearing a representation of an object, portions of said representation corresponding to adjacent rows of elemental areas of which said object is composed being laterally displaced relatively to one another on said film, the provision in a longitudinal direction on said film of a continuous representation of the brightness of each of said elemental areas.

2. In a motion picture film bearing a representation of an object, portions of said representation corresponding to vertically related horizontal rows of elemental areas of which the Object is composed being laterally oiTset on said film, the provision in a longitudinal direction on said film of a continuous representation of the brightness of each of said elemental areas.

3. A motion picture record comprising an elongated carrier bearing markings representative of a two-dimensional image, changes in density of said markings along any line parallel to the length dimension of said carrier being representative of changes in brightness of an individual elemental area of said two dimensional image with time.

4. A motion picture record comprising an elongated carrier bearing a multiplicity of markings each representative of one of a multiplicity of elemental areas of which the recorded picture is composed, said markings being, in the record, arranged side by side transverse of said carrier and extending longitudinally of said carrier and changes in density of each of said markings along the length thereof being representative of changes in brightness of the elemental area represented thereby with time.

GEORGE WILLIAM WALTON. 

